113 results on '"McKay, Ryan"'
Search Results
2. 'So Help Me God'? Does oath swearing in courtroom scenarios impact trial outcomes?
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McKay, Ryan T., Gervais, Will, and Davis, Colin J.
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JURY ethics , *RESEARCH , *ETHICS , *WITNESSES , *HONESTY , *AUDIOVISUAL materials , *PREJUDICES , *COURTS , *DECISION making , *RESEARCH funding , *CASE studies , *PSYCHOSOCIAL factors , *LEGAL procedure , *JURY , *RELIGION - Abstract
In countries such as Britain and the US, court witnesses must declare they will provide truthful evidence and are often compelled to publicly choose between religious ("oath") and secular ("affirmation") versions of this declaration. Might defendants who opt to swear an oath enjoy more favourable outcomes than those who choose to affirm? Two preliminary, pre‐registered survey studies using minimal vignettes (Study 1, N = 443; Study 2, N = 913) indicated that people associate choice of the oath with credible testimony; and that participants, especially religious participants, discriminate against defendants who affirm. In a third, Registered Report study (Study 3, N = 1821), we used a more elaborate audiovisual mock trial paradigm to better estimate the real‐world influence of declaration choice. Participants were asked to render a verdict for a defendant who either swore or affirmed, and were themselves required to swear or affirm that they would try the defendant in good faith. Overall, the defendant was not considered guiltier when affirming rather than swearing, nor did mock‐juror belief in God moderate this effect. However, jurors who themselves swore an oath did discriminate against the affirming defendant. Exploratory analyses suggest this effect may be driven by authoritarianism, perhaps because high‐authoritarian jurors consider the oath the traditional (and therefore correct) declaration to choose. We discuss the real‐world implications of these findings and conclude the religious oath is an antiquated legal ritual that needs reform. [ABSTRACT FROM AUTHOR]
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- 2023
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3. The sound of swearing: Are there universal patterns in profanity?
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Lev-Ari, Shiri and McKay, Ryan
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SWEARING (Profanity) , *SOUND symbolism , *NATIVE language , *CHINESE language , *GERMAN language - Abstract
Why do swear words sound the way they do? Swear words are often thought to have sounds that render them especially fit for purpose, facilitating the expression of emotion and attitude. To date, however, there has been no systematic cross-linguistic investigation of phonetic patterns in profanity. In an initial, pilot study we explored statistical regularities in the sounds of swear words across a range of typologically distant languages. The best candidate for a cross-linguistic phonemic pattern in profanity was the absence of approximants (sonorous sounds like l, r, w and y). In Study 1, native speakers of various languages (Arabic, Chinese, Finnish, French, German, Spanish; N = 215) judged foreign words less likely to be swear words if they contained an approximant. In Study 2 we found that sanitized versions of English swear words – like darn instead of damn – contain significantly more approximants than the original swear words. Our findings reveal that not all sounds are equally suitable for profanity, and demonstrate that sound symbolism – wherein certain sounds are intrinsically associated with certain meanings – is more pervasive than has previously been appreciated, extending beyond denoting single concepts to serving pragmatic functions. [ABSTRACT FROM AUTHOR]
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- 2023
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4. Delusions as Epistemic Hypervigilance.
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McKay, Ryan and Mercier, Hugo
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DELUSIONS , *SKEPTICISM , *CONTRADICTION , *SYMPTOMS , *SENSES , *NEUROLEPTIC malignant syndrome - Abstract
Delusions are distressing and disabling symptoms of various clinical disorders. Delusions are associated with an aberrant and apparently contradictory treatment of evidence, characterized by both excessive credulity (adopting unusual beliefs on minimal evidence) and excessive rigidity (holding steadfast to these beliefs in the face of strong counterevidence). Here we attempt to make sense of this contradiction by considering the literature on epistemic vigilance. Although there is little evolutionary advantage to scrutinizing the evidence our senses provide, it pays to be vigilant toward ostensive evidence—information communicated by others. This asymmetry is generally adaptive, but in deluded individuals the scales tip too far in the direction of the sensory and perceptual, producing an apparently paradoxical combination of credulity (with respect to one's own perception) and skepticism (with respect to the testimony of others). [ABSTRACT FROM AUTHOR]
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- 2023
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5. COVID-19 and seasonal flu vaccination hesitancy: Links to personality and general intelligence in a large, UK cohort.
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Halstead, Isaac N., McKay, Ryan T., and Lewis, Gary J.
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INFLUENZA vaccines , *FIVE-factor model of personality , *INFLUENZA , *HESITATION , *SWINE influenza , *COVID-19 vaccines , *PERSONALITY - Abstract
Vaccines are a powerful and relatively safe tool to protect against a range of serious diseases. Nonetheless, a sizeable minority of people express 'vaccination hesitancy'. Accordingly, understanding the bases of this hesitancy represents a significant public health opportunity. In the present study we sought to examine the role of Big Five personality traits and general intelligence as predictors of vaccination hesitancy across two vaccination types in a large (N = 9667) sample of UK adults drawn from the Understanding Society longitudinal household study. We found that lower levels of general intelligence were associated with COVID-19 and seasonal flu vaccination hesitancy, and lower levels of neuroticism was associated with COVID-19 vaccination hesitancy. Although the self-reported reasons for being vaccine hesitant indicated a range of factors were important to people, lower general intelligence was associated with virtually all of these reasons. In contrast, Big Five personality traits showed more nuanced patterns of association. [ABSTRACT FROM AUTHOR]
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- 2022
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6. Explaining human sampling rates across different decision domains.
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van de Wouw, Didrika S., McKay, Ryan T., Averbeck, Bruno B., and Furl, Nicholas
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FACE , *HUMAN beings , *DECISION making - Abstract
Undersampling biases are common in the optimal stopping literature, especially for economic full choice problems. Among these kinds of number-based studies, the moments of the distribution of values that generates the options (i.e., the generating distribution) seem to influence participants’ sampling rate. However, a recent study reported an oversampling bias on a different kind of optimal stopping task: where participants chose potential romantic partners from images of faces (Furl et al., 2019). The authors hypothesised that this oversampling bias might be specific to mate choice. We preregistered this hypothesis and so, here, we test whether sampling rates across different image-based decision-making domains a) reflect different over- or undersampling biases, or b) depend on the moments of the generating distributions (as shown for economic number-based tasks). In two studies (N = 208 and N = 96), we found evidence against the preregistered hypothesis. Participants oversampled to the same degree across domains (compared to a Bayesian ideal observer model), while their sampling rates depended on the generating distribution mean and skewness in a similar way as number-based paradigms. Moreover, optimality model sampling to some extent depended on the the skewness of the generating distribution in a similar way to participants. We conclude that oversampling is not instigated by the mate choice domain and that sampling rate in image-based paradigms, like number-based paradigms, depends on the generating distribution. [ABSTRACT FROM AUTHOR]
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- 2022
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7. Individuals with adverse childhood experiences explore less and underweight reward feedback.
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Lloyd, Alex, McKay, Ryan Thomas, and Furl, Nicholas
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ADVERSE childhood experiences , *REWARD (Psychology) , *MALNUTRITION - Abstract
Adverse childhood experiences (ACEs) are extreme stressors that lead to negative psychosocial outcomes in adulthood. Nonhuman animals explore less after exposure to early stress. Therefore, in this preregistered study, we hypothesized that reduced exploration following ACEs would also be evident in human adults. Further, we predicted that adults with ACEs, in a foraging task, would adopt a decision-making policy that relies on the most-recent reward feedback, a rational strategy for unstable environments. We analyzed data from 145 adult participants, 47 with four or more ACEs and 98 with fewer than four ACEs. In the foraging task, participants evaluated the trade-off between exploiting a known patch with diminishing rewards and exploring a novel one with a fresh distribution of rewards. Using computational modeling, we quantified the degree to which participants' decisions weighted recent feedback. As predicted, participants with ACEs explored less. However, contrary to our hypothesis, they underweighted recent feedback. These unexpected findings indicate that early adversity may dampen reward sensitivity. Our results may help to identify cognitive mechanisms that link childhood trauma to the onset of psychopathology. [ABSTRACT FROM AUTHOR]
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- 2022
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8. What is the extent of a frequency-dependent social learning strategy space?
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Bellamy, Aysha, McKay, Ryan, Vogt, Sonja, and Efferson, Charles
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- 2022
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9. Continuity and credibility in the Cognitive Science of Religion.
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Ross, Robert M. and McKay, Ryan
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- 2021
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10. Delay discounting and under-valuing of recent information predict poorer adherence to social distancing measures during the COVID-19 pandemic.
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Lloyd, Alex, McKay, Ryan, Hartman, Todd K., Vincent, Benjamin T., Murphy, Jamie, Gibson-Miller, Jilly, Levita, Liat, Bennett, Kate, McBride, Orla, Martinez, Anton P., Stocks, Thomas V. A., Vallières, Frédérique, Hyland, Philip, Karatzias, Thanos, Butter, Sarah, Shevlin, Mark, Bentall, Richard P., and Mason, Liam
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SOCIAL distancing , *DELAY discounting (Psychology) , *COVID-19 pandemic , *SOCIAL anxiety , *MENTAL illness , *REWARD (Psychology) - Abstract
The COVID-19 pandemic has brought about unprecedented global changes in individual and collective behaviour. To reduce the spread of the virus, public health bodies have promoted social distancing measures while attempting to mitigate their mental health consequences. The current study aimed to identify cognitive predictors of social distancing adherence and mental health symptoms, using computational models derived from delay discounting (the preference for smaller, immediate rewards over larger, delayed rewards) and patch foraging (the ability to trade-off between exploiting a known resource and exploring an unknown one). In a representative sample of the UK population (N = 442), we find that steeper delay discounting predicted poorer adherence to social distancing measures and greater sensitivity to reward magnitude during delay discounting predicted higher levels of anxiety symptoms. Furthermore, under-valuing recently sampled information during foraging independently predicted greater violation of lockdown guidance. Our results suggest that those who show greater discounting of delayed rewards struggle to maintain social distancing. Further, those who adapt faster to new information are better equipped to change their behaviour in response to public health measures. These findings can inform interventions that seek to increase compliance with social distancing measures whilst minimising negative repercussions for mental health. [ABSTRACT FROM AUTHOR]
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- 2021
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11. Are adolescents more optimal decision‐makers in novel environments? Examining the benefits of heightened exploration in a patch foraging paradigm.
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Lloyd, Alex, McKay, Ryan, Sebastian, Catherine L., and Balsters, Joshua H.
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TEENAGERS , *ADULTS , *ADOLESCENCE - Abstract
Adolescence is a period of heightened exploration relative to adulthood and childhood. This predisposition has been linked with negative behaviours related to risk‐taking, including dangerous driving, substance misuse and risky sexual practices. However, recent models have argued that adolescents' heightened exploration serves a functional purpose within the lifespan, allowing adolescents to develop experiential knowledge of their surroundings. Yet, there is limited evidence that heightened exploration in adolescence is associated with positive outcomes. To address this, the present pre‐registered study utilised a foraging paradigm with a sample of adolescents aged 16–17 (N = 68) and of adults aged 21 and above (N = 69). Participants completed a patch foraging task, which required them to choose between exploiting a known resource which gradually yields fewer rewards, and exploring a novel, unknown resource with a fresh distribution of rewards. Findings demonstrated that adolescents explored more than adults, which – in the context of the current task—represented more optimal patch foraging behaviour. These findings indicate that adolescents' heightened exploration can be beneficial, as they were able to effectively navigate unknown environments and accrue rewards more successfully than adults. This provides evidence that heightened exploration in adolescence, relative to adulthood, can lead to positive outcomes and contributes to our understanding of the role increased novelty‐seeking plays at this point in the lifespan. [ABSTRACT FROM AUTHOR]
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- 2021
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12. The evolution of distorted beliefs vs. mistaken choices under asymmetric error costs.
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Efferson, Charles, McKay, Ryan, and Fehr, Ernst
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- 2020
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13. Explaining delusional beliefs: a hybrid model.
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Miyazono, Kengo and McKay, Ryan
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DELUSIONS , *ERROR analysis in mathematics , *PREDICTION theory , *IDEA (Philosophy) - Abstract
Introduction: In this paper we present and defend a hybrid theory of the development of delusions that incorporates the central ideas of two influential (yet sometimes bitterly opposing) theoretical approaches to delusions—the two-factor theory and the prediction error theory. Method: After introducing the central ideas of the two-factor theory and the prediction error theory, we describe the motivations for our conciliatory project, explain the theoretical details of the hybrid theory we propose, and answer potential objections to our proposal. Results: According to the hybrid theory we advance, the first factor of a delusion is physically grounded in an abnormal prediction error, and the second factor is physically grounded in the overestimation of the precision of the abnormal prediction error. Against anticipated objections, we argue that the hybrid theory is internally coherent, and that it constitutes a genuine hybrid between the two-factor theory and the prediction error theory. Conclusion: A rapprochement between the two-factor theory and the prediction error theory is both possible and desirable. In particular, our hybrid theory provides a parsimonious and unified account of delusions, whether monothematic or polythematic, across a wide variety of medical conditions. [ABSTRACT FROM AUTHOR]
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- 2019
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14. Measles, magic and misidentifications: a defence of the two-factor theory of delusions.
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McKay, Ryan
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DELUSIONS , *PSYCHOPHYSIOLOGY , *GALVANIC skin response , *MEASLES , *BRAIN damaged patients , *PREDICTION theory - Abstract
Corlett (Corlett, P. (this issue). Factor one, familiarity and frontal cortex: A challenge to the two-factor theory of delusions. Cognitive Neuropsychiatry) provides a robust critique of the two-factor theory of delusions. The heart of his critique is two challenges he derives from a paper by Tranel and Damasio (Tranel, D., & Damasio, H. (1994). Neuroanatomical correlates of electrodermal skin conductance responses. Psychophysiology, 31(5), 427–438), who illuminate the autonomic responses and brain damage of four patients often cited in support of the two-factor theory of Capgras delusion. I defend the two-factor theory against Corlett's two key challenges, arguing that his first challenge has been previously addressed, and that his second challenge is overstated. In my view, these challenges do not negate the two-factor account. Nevertheless, two-factor theorists – and computational psychiatrists – should continue to devise and test falsifiable predictions of their respective theories. [ABSTRACT FROM AUTHOR]
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- 2019
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15. Diverse residues of intracellular loop 5 of the Na+/H+ exchanger modulate proton sensing, expression, activity and targeting.
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Wong, Ka Yee, McKay, Ryan, Liu, Yongsheng, Towle, Kaitlyn, Elloumi, Yesmine, Li, Xiuju, Quan, Sicheng, Dutta, Debajyoti, Sykes, Brian D., and Fliegel, Larry
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INTRACELLULAR membranes , *PROTON detection , *MEMBRANE proteins , *BREAST cancer , *NUCLEAR magnetic resonance - Abstract
Abstract The mammalian Na+/H+ exchanger isoform 1 (NHE1) is an integral membrane protein that regulates intracellular pH (pH i) by removing a single intracellular proton in exchange for one extracellular sodium ion. It is involved in cardiac hypertrophy and ischemia reperfusion damage to the heart and elevation of its activity is a trigger for breast cancer metastasis. NHE1 has an extensive 500 amino acid N-terminal membrane domain that mediates transport and consists of 12 transmembrane segments connected by intracellular and extracellular loops. Intracellular loops are hypothesized to modulate the sensitivity to pH i. In this study, we characterized the structure and function of intracellular loop 5 (IL5), specifically amino acids 431–443. Mutation of eleven residues to alanine caused partial or nearly complete inhibition of transport; notably, mutation of residues L432, T433, I436, N437, R440 and K443 demonstrated these residues had critical roles in NHE1 function independent of effects on targeting or expression. The nuclear magnetic resonance (NMR) solution spectra of the IL5 peptide in a membrane mimetic sodium dodecyl sulfate solution revealed that IL5 has a stable three-dimensional structure with substantial alpha helical character. NMR chemical shifts indicated that K438 was in close proximity with W434. Overall, our results show that IL5 is a critical, intracellular loop with a propensity to form an alpha helix, and many residues of this intracellular loop are critical to proton sensing and ion transport. Graphical abstract Unlabelled Image Highlights • Intracellular loop 5 (IL5) of the mammalian Na+/H+ exchanger isoform one was studied. • Mutation of 11 residues to Ala caused partial or near complete inhibition of NHE1. • Residues L432, T433, I436, N437, R440 and K443 had critical roles in activity of NHE1. • IL5 peptide in has a propensity towards alpha helical character. • NMR chemical shifts indicate that K438 is in close proximity with W434. [ABSTRACT FROM AUTHOR]
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- 2019
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16. A platform of genetically engineered bacteria as vehicles for localized delivery of therapeutics: Toward applications for Crohn's disease.
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McKay, Ryan, Ghodasra, Monil, Schardt, John, Quan, David, Pottash, Alex Eli, Shang, Wu, Jay, Steven M., Payne, Gregory F., Chang, Matthew Wook, March, John C., and Bentley, William E.
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GENETICS of Crohn's disease , *GENETIC engineering , *BACTERIAL genes , *DRUG delivery systems , *GENE targeting , *GASTROINTESTINAL disease treatment - Abstract
For therapies targeting diseases of the gastrointestinal tract, we and others envision probiotic bacteria that synthesize and excrete biotherapeutics at disease sites. Toward this goal, we have engineered commensal E. coli that selectively synthesize and secrete a model biotherapeutic in the presence of nitric oxide (NO), an intestinal biomarker for Crohn's disease (CD). This is accomplished by co‐expressing the pore forming protein TolAIII with the biologic, granulocyte macrophage‐colony stimulating factor (GM‐CSF). We have additionally engineered these bacteria to accumulate at sites of elevated NO by engineering their motility circuits and controlling pseudotaxis. Importantly, because we have focused on in vitro test beds, motility and biotherapeutics production are spatiotemporally characterized. Together, the targeted recognition, synthesis, and biomolecule delivery comprises a "smart" probiotics platform that may have utility in the treatment of CD. Further, this platform could be modified to accommodate other pursuits by swapping the promoter and therapeutic gene to reflect other disease biomarkers and treatments, respectively. Here, we engineer commensal E. coli to overproduce and secrete a model biotherapeutic, granulocyte macrophage colony stimulating factor (GM‐CSF) in response to the Crohn's disease (CD) biomarker, nitric oxide. The GM‐CSF protein has shown utility as a therapy for CD, and thus the bacteria developed here may serve as a noninvasive method to localize drug delivery within the intestines of patients. Using the platform outlined in this work, replacing the biotherapeutic gene with another of interest can produce engineered probiotics that secrete therapies for other diseases. [ABSTRACT FROM AUTHOR]
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- 2018
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17. Not on my team: Medial prefrontal cortex responses to ingroup fusion and unfair monetary divisions.
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Apps, Matthew A. J., McKay, Ryan, Azevedo, Ruben T., Whitehouse, Harvey, and Tsakiris, Manos
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PREFRONTAL cortex , *JUDGMENT (Psychology) , *GROUP identity , *MAGNETIC resonance imaging of the brain , *INTERPERSONAL relations - Abstract
Abstract: Objective: People are highly attuned to fairness, with people willingly suffering personal costs to prevent others benefitting from unfair acts. Are fairness judgments influenced by group alignments? A new theory posits that we favor ingroups and denigrate members of rival outgroups when our personal identity is fused to a group. Although the mPFC has been separately implicated in group membership and fairness processing, it is unclear whether group alignments affect medial prefrontal cortex (mPFC) activity in response to fairness. Here, we examine the contribution of different regions of the mPFC to processing from ingroup and outgroup members and test whether its response differs depending on how fused we are to an ingroup. Methods: Subjects performed rounds of the Ultimatum Game, being offered fair or unfair divisions of money from supporters of the same soccer team (ingroup), the fiercest rival (outgroup) or neutral individuals whilst undergoing functional Magnetic Resonance Imaging (fMRI). Results: Strikingly, people willingly suffered personal costs to prevent outgroup members benefitting from both unfair and fair offers. Activity across dorsal and ventral (VMPFC) portions of the mPFC reflected an interaction between fairness and group membership. VMPFC activity in particular was consistent with it coding one's fusion to a group, with the fairness by group membership interaction correlating with the extent that the responder's identity was fused to the ingroup. Conclusions: The influence of fusion on social behavior therefore seems to be linked to processing in the VMPFC. [ABSTRACT FROM AUTHOR]
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- 2018
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18. Understanding patch foraging strategies across development.
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Lloyd, Alex, Viding, Essi, McKay, Ryan, and Furl, Nicholas
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CONTROL (Psychology) , *REWARD (Psychology) , *COGNITIVE ability , *MENTAL illness , *MENTAL health - Abstract
From adolescence to adulthood, there is a decrease in exploration choices in foraging decision-making problems. In youth, a disposition to explore when faced with explore/exploit choices can support the individual to learn the structure of their environment, enabling them to effectively exploit rewards in maturity. Such age-related differences are likely driven by neurocognitive changes to reward processing, learning, and cognitive control across development. Individual differences in foraging strategies can be indicative of cognitive biases implicated in mental health outcomes. Patch foraging is a near-ubiquitous behaviour across the animal kingdom and characterises many decision-making domains encountered by humans. We review how a disposition to explore in adolescence may reflect the evolutionary conditions under which hunter-gatherers foraged for resources. We propose that neurocomputational mechanisms responsible for reward processing, learning, and cognitive control facilitate the transition from exploratory strategies in adolescence to exploitative strategies in adulthood – where individuals capitalise on known resources. This developmental transition may be disrupted by psychopathology, as there is emerging evidence of biases in explore/exploit choices in mental health problems. Explore/exploit choices may be an informative marker for mental health across development and future research should consider this feature of decision-making as a target for clinical intervention. [ABSTRACT FROM AUTHOR]
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- 2023
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19. Idolizing the indexical: commentary on Van Leeuwen and van Elk.
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McKay, Ryan, Jong, Jonathan, and O'Lone, Katherine
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- 2019
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20. Rituals Improve Children's Ability to Delay Gratification.
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Rybanska, Veronika, McKay, Ryan, Jong, Jonathan, and Whitehouse, Harvey
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DELAY of gratification , *RITES & ceremonies , *SOCIAL groups , *INTERNALIZATION (Social psychology) , *SELF regulation - Abstract
To be accepted into social groups, individuals must internalize and reproduce appropriate group conventions, such as rituals. The copying of such rigid and socially stipulated behavioral sequences places heavy demands on executive function. Given previous research showing that challenging executive functioning improves it, it was hypothesized that engagement in ritualistic behaviors improves children's executive functioning, in turn improving their ability to delay gratification. A 3-month circle time games intervention with 210 schoolchildren (Mage = 7.78 years, SD = 1.47) in two contrasting cultural environments (Slovakia and Vanuatu) was conducted. The intervention improved children's executive function and in turn their ability to delay gratification. Moreover, these effects were amplified when the intervention task was imbued with ritual, rather than instrumental, cues. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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21. Why is belief in God not a delusion?
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Ross, Robert M. and McKay, Ryan
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- 2017
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22. The optimist within? Selective sampling and self-deception.
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van der Leer, Leslie and McKay, Ryan
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OPTIMISM , *SELF-deception , *DEFLATIONARY theory of truth - Abstract
The nature and existence of self-deception is controversial. On a classic conception, self-deceived individuals carry two conflicting representations of reality. Proponents of an alternative, deflationary account dispute this, arguing that putative cases of self-deception simply reflect distorted information processing. To investigate these alternatives, we adapted a paradigm from the “crowd-within” literature. Participants provided two different estimates for each of a series of incentivized questions. Half of the questions were neutral in content, while half referred to undesirable future events. Whereas the first and second estimates for neutral questions did not differ systematically, second estimates for undesirable questions were more optimistic than first estimates. This result suggests that participants were sampling selectively from an internal probability distribution when providing estimates for undesirable events, implying they had access to a less rosy representation of their future prospects than their individual estimates conveyed. In short, self-deception is real. [ABSTRACT FROM AUTHOR]
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- 2017
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23. Doppelgängers and dissociations: lesion network mapping illuminates misidentification delusions.
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McKay, Ryan and Furl, Nicholas
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DELUSIONS , *NEUROPSYCHOLOGICAL tests - Published
- 2017
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24. DIVINE FORGIVENESS AND HUMAN SUPPORT FOR STATE-SANCTIONED PUNISHMENT.
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O'LONE, KATHERINE M. and MCKAY, RYAN T.
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PUNISHMENT , *FORGIVENESS , *GODS , *BELIEF & doubt , *RESPONSIBILITY - Abstract
Laurin et al. 2012b found that beliefs in powerful Gods (both in general and when made salient) reduce people's endorsement of state-sanctioned punishment. Here we investigate whether the specific manner in which a powerful God responds to moral infractions (via forgiveness or punishment) influences people's endorsement of state-sanctioned punishment. Across four studies, we explored whether endorsement of state-sanctioned punishment is increased a) when participants are primed with the notion of a forgiving (cf. punitive) God (Studies 1 & 2) and b) when beliefs in a forgiving God are made salient (Studies 3a & 3b). A forgiving God might lead people to view punishment as their responsibility rather than one to be outsourced to God. Our results revealed no evidence for effects of forgiving God primes or salient forgiving God beliefs on endorsement of state-sanctioned punishment. However we did find that both forgiving and punishing God beliefs, when salient, were significant predictors of endorsement of state-sanctioned punishment in response to a victim-directed transgression. We discuss the implications of these findings for extant theories of religious prosociality. In particular, we suggest that existing accounts of human prosociality and cooperation have underestimated the role of divine forgiveness in favour of a focus on divine punishment. [ABSTRACT FROM AUTHOR]
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- 2016
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25. Bayesian accounts and black swans: Questioning the erotetic theory of delusional thinking.
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McKay, Ryan
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DELUSIONS , *COGNITION disorders , *THOUGHT & thinking , *SCHIZOPHRENIA , *MENTAL illness - Abstract
Parrott and Koralus argue that a particular cognitive factor – “impaired endogenous question raising” – offers a parsimonious account of three delusion-related phenomena: (1) the development of the Capgras delusion; (2) evidence that patients with schizophrenia outperform healthy control participants on a conditional reasoning task; and (3) evidence that deluded individuals “jump to conclusions”. In this response, I assess these claims, and raise my own questions about the “erotetic” theory of delusional thinking. [ABSTRACT FROM AUTHOR]
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- 2015
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26. Religion and Morality.
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McKay, Ryan and Whitehouse, Harvey
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RELIGION & ethics , *COGNITION & culture , *PROSOCIAL behavior , *COGNITION research - Abstract
The relationship between religion and morality has long been hotly debated. Does religion make us more moral? Is it necessary for morality? Do moral inclinations emerge independently of religious intuitions? These debates, which nowadays rumble on in scientific journals as well as in public life, have frequently been marred by a series of conceptual confusions and limitations. Many scientific investigations have failed to decompose "religion" and "morality" into theoretically grounded elements; have adopted parochial conceptions of key concepts--in particular, sanitized conceptions of "prosocial" behavior; and have neglected to consider the complex interplay between cognition and culture. We argue that to make progress, the categories "religion" and "morality" must be fractionated into a set of biologically and psychologically cogent traits, revealing the cognitive foundations that shape and constrain relevant cultural variants. We adopt this fractionating strategy, setting out an encompassing evolutionary framework within which to situate and evaluate relevant evidence. Our goals are twofold: to produce a detailed picture of the current state of the field, and to provide a road map for future research on the relationship between religion and morality. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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27. Religion and Agency.
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McKay, Ryan
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RELIGION & science , *AGENT (Philosophy) , *ELECTROENCEPHALOGRAPHY - Abstract
An introduction to the journal is presented which discusses various papers published within the issue, including one on whether activating religious concepts improves the ascription of agency to natural phenomena and another on an electroencephalography study using a placebo God Helmet.
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- 2014
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28. "Jumping to conclusions" in delusion-prone participants: an experimental economics approach.
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van der Leer, Leslie and McKay, Ryan
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TASK performance , *EXPERIMENTAL economics , *MONETARY incentives , *PAY for performance , *COGNITION disorders - Abstract
Introduction: That delusional and delusion-prone individuals "jump to conclusions" on probabilistic reasoning tasks is a key finding in cognitive neuropsychiatry. Here we focused on a less frequently investigated aspect of "jumping to conclusions" (JTC): certainty judgments. We incorporated rigorous procedures from experimental economics to eliminate potential confounds of miscomprehension and motivation and systematically investigated the effect of incentives on task performance. Methods: Low- and high-delusion-prone participants (n = 109) completed a series of computerised trials; on each trial, they were shown a black or a white fish, caught from one of the two lakes containing fish of both colours in complementary ratios. In the betting condition, participants were given £4 to distribute over the two lakes as they wished; in the control condition, participants simply provided an estimate of how probable each lake was. Deviations from Bayesian probabilities were investigated. Results: Whereas high-delusion-prone participants in both the control and betting conditions underestimated the Bayesian probabilities (i.e. were conservative), low- delusion-prone participants in the control condition underestimated but those in the betting condition provided accurate estimates. In the control condition, there was a trend for high-delusion-prone participants to give higher estimates than low-dclusion- prone participants, which is consistent with previous reports of "jumping to conclusions" in delusion-prone participants. However, our findings in the betting condition, where high-delusion-prone participants provided lower estimates than low- delusion-prone participants (who were accurate), are inconsistent with the jumping-to- conclusions effect in both a relative and an absolute sense. Conclusions: Our findings highlight the key role of task incentives and underscore the importance of comparing the responses of delusion-prone participants to an objective rational standard as well as to the responses of non-delusion-prone participants. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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29. Paranoid males have reduced lateralisation for processing of negative emotions: An investigation using the chimeric faces test.
- Author
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Bourne, Victoria J. and McKay, Ryan T.
- Subjects
- *
LATERAL dominance , *PEOPLE with schizophrenia , *CEREBRAL dominance , *DUAL-brain psychology , *EMOTIONS - Abstract
Reduced strength of lateralisation in patients with schizophrenia has been reported in a number of studies. However the exact nature of this relationship remains unclear. In this study, lateralisation for processing emotional faces was measured using the chimeric faces test and examined in relation to paranoia in a non-clinical sample. For males only, those with higher scores on a paranoia questionnaire had reduced lateralisation for processing negative facial emotion. For females there were no significant relationships. These findings suggest that atypical patterns of lateralisation for processing emotional stimuli may be implicated in, or associated with, increased levels of paranoia. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
30. Signal Intensities Derived from Different NMR Probes and Parameters Contribute to Variations in Quantification of Metabolites.
- Author
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Lacy, Paige, McKay, Ryan T., Finkel, Michael, Karnovsky, Alla, Woehler, Scott, Lewis, Michael J., Chang, David, and Stringer, Kathleen A.
- Subjects
- *
MOLECULAR probes , *BIOMARKERS , *URINALYSIS , *NUCLEAR magnetic resonance spectroscopy , *METABOLOMICS , *QUANTITATIVE research - Abstract
We discovered that serious issues could arise that may complicate interpretation of metabolomic data when identical samples are analyzed at more than one NMR facility, or using slightly different NMR parameters on the same instrument. This is important because cross-center validation metabolomics studies are essential for the reliable application of metabolomics to clinical biomarker discovery. To test the reproducibility of quantified metabolite data at multiple sites, technical replicates of urine samples were assayed by 1D-1H-NMR at the University of Alberta and the University of Michigan. Urine samples were obtained from healthy controls under a standard operating procedure for collection and processing. Subsequent analysis using standard statistical techniques revealed that quantitative data across sites can be achieved, but also that previously unrecognized NMR parameter differences can dramatically and widely perturb results. We present here a confirmed validation of NMR analysis at two sites, and report the range and magnitude that common NMR parameters involved in solvent suppression can have on quantitated metabolomics data. Specifically, saturation power levels greatly influenced peak height intensities in a frequency-dependent manner for a number of metabolites, which markedly impacted the quantification of metabolites. We also investigated other NMR parameters to determine their effects on further quantitative accuracy and precision. Collectively, these findings highlight the importance of and need for consistent use of NMR parameter settings within and across centers in order to generate reliable, reproducible quantified NMR metabolomics data. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
31. Understanding the variability of compound quantification from targeted profiling metabolomics of 1D-H-NMR spectra in synthetic mixtures and urine with additional insights on choice of pulse sequences and robotic sampling.
- Author
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Sokolenko, Stanislav, McKay, Ryan, Blondeel, Eric, Lewis, Michael, Chang, David, George, Ben, and Aucoin, Marc
- Subjects
- *
NUCLEAR magnetic resonance spectroscopy , *METABOLOMICS , *URINE , *SPECTRUM analysis , *DECONVOLUTION (Mathematics) , *PULSE (Heart beat) , *MEDICAL screening - Abstract
The growing use of 'targeted profiling' approaches for the deconvolution of 1D-H-NMR spectra by comparison to a pure compound library has created a need for an in-depth characterization of quantification variability that is beyond what is currently available in the literature. In this study, we explore the underlying source of quantification variability (tube insertion, spectra acquisition, and profiling) as well as a number of other factors, such as temporal consistency of repeated NMR scans, human consistency in repeated profiles, and human versus machine sampling. We also look at the effect of different pulse sequences on the differences between acquired spectra and the peak reference library. Two sample types were considered for this work-a synthetic five compound mixture as well as human urine. The result is a comprehensive examination of 1D-H-NMR quantification error. Our investigation into variability sources revealed that apart from profiling, sample insertion and/or shimming can play a significant role in final quantification, a finding that is equally applicable to all integration-based methods of quantification. Both sources of error were also found to have temporal relationships, with bias identified as a function of both scan and profiling order, reinforcing the need for randomization in scanning and profiling. As well as presenting a practical estimate of variability in human urine samples, we have uncovered a considerable amount of complexity in underlying NMR variability that will hopefully serve as impetus for future exploration in this area. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
32. Do Religious and Moral Concepts Influence the Ability to Delay Gratification? A Priming Study.
- Author
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Harrison, Justin Marc David and McKay, Ryan Thomas
- Subjects
- *
DELAY of gratification , *SELF-control , *ETHICS , *PRIMING (Psychology) , *MOTIVATION (Psychology) - Abstract
Rounding, Lee, Jacobsen and Ji (2012) reported that priming with religious concepts increases the ability to delay gratification, an interpretation that implies decreased temporal discounting. The required magnitude of such a decrease--to make participants respond in the way Rounding et al. report--is very large, and should be easily detectable. Sixty-nine participants were allocated to religious, secular moral (Fairness) or neutral priming conditions. Temporal discounting rates were estimated for each participant using an 'Equivalent Present Value' procedure prior to and following the sentence unscrambling primes. No effects for priming conditions were detected. With regard to theoretical explanations for the results, we suggest that it is not the ability--but motivation--to delay gratiication that is influenced by religious concepts. [ABSTRACT FROM AUTHOR]
- Published
- 2013
33. Delusional Inference.
- Author
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MCKAY, RYAN
- Subjects
- *
DELUSIONS , *REASONING , *BAYESIAN analysis , *NUMERICAL analysis , *REASON - Abstract
Does the formation of delusions involve abnormal reasoning? According to the prominent 'two-factor' theory of delusions (e.g. Coltheart, 2007), the answer is yes. The second factor in this theory is supposed to affect a deluded individual's ability to evaluate candidates for belief. However, most published accounts of the two-factor theory have not said much about the nature of this second factor. In an effort to remedy this shortcoming, Coltheart, Menzies and Sutton (2010) recently put forward a Bayesian account of inference in delusions. I outline some criticisms of this important account, and sketch an alternative account of delusional inference that, I argue, avoids these criticisms. Specifically, I argue that the second factor in delusion formation involves a systematic deviation from Bayesian updating, a deviation that may be characterized as a bias towards 'explanatory adequacy'. I present a numerical model of this idea and show that my alternative account is broadly consistent with prominent prediction error models of delusion formation (e.g. Corlett, Murray et al., 2007). [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
34. DELAY DISCOUNTING RATES ARE TEMPORALLY STABLE IN AN EQUIVALENT PRESENT VALUE PROCEDURE USING THEORETICAL AND AREA UNDER THE CURVE ANALYSES.
- Author
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Harrison, Justin and McKay, Ryan
- Subjects
- *
SOCIAL science research , *UNIVERSITIES & colleges , *STATISTICAL reliability , *MATHEMATICAL models - Abstract
Temporal discounting rates have become a popular dependent variable in social science research. While choice procedures are commonly employed to measure discounting rates, equivalent present value (EPV) procedures may be more sensitive to experimental manipulation. However, their use has been impeded by the absence of test-retest reliability data. Staff and students at a regional Australian university (n = 53) participated in a matching EPV temporal discounting procedure in 2 sessions, 2 weeks apart, completing 30 one-shot, second-price auctions for two amounts, with delays ranging from 1-43 days. Discounting rates were estimated using hyperbolic and exponential models, as well as atheoretical area under the curve (AuC) analyses. Test-retest (relative) stability of the EPV procedure compared favorably with choice procedures (r = .75). Where discounting rates are used as a dependent variable, brief EPV procedures combined with atheoretical analyses of discounting rates are a more sensitive means to detect subtle experimental effects. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
35. The 3D Structure of Thuricin CD, a Two-Component Bacteriocin with Cysteine Sulfur to α-Carbon Cross-links.
- Author
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Sit, Clarissa S., McKay, Ryan T., Hill, Cohn, Ross, R. Paul, and Vederas, John C.
- Subjects
- *
BACTERIOCINS , *THREE-dimensional imaging , *ANTI-infective agents , *CLOSTRIDIOIDES difficile , *CYSTEINE desulfurase , *STEREOCHEMISTRY , *STEREOISOMERS , *NUCLEAR magnetic resonance spectroscopy - Abstract
Thuricin CD is an antimicrobial factor that consists of two peptides, Tm-α and Trn-β, that exhibit synergistic activity against drug resistant strains of Clostridium difficile. Tm-α and Tm-β each possess three sulfur to α-carbon thioether bridges for which the stereochemistry is unknown. This report presents the three-dimensional solution structures of Tm-α and Tm-β. Structure calculations were performed for the eight possible stereoisomers of each peptide based on the same NMR data. The structure of the stereoisomer that best fit the experimental data was chosen as the representative structure for each peptide. It was determined that Trn-α. has L-stereochemlstry at SerZl (α- R), L-stereochemistry at Thr2S (α-R), and n-stereochemis- try at Thr28 (α-S) (an LLD isomer). Trn-β was also found to be the LLD isomer, with L-stereochemistry at ThrZl (α- R), L-stereochemistry at Thr25(α-R), and D-stereochemistry at Tyr28 (α-S). [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
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36. Confabulation, delusion, and anosognosia: Motivational factors and false claims.
- Author
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McKay, Ryan and Kinsbourne, Marcel
- Subjects
- *
ANOSOGNOSIA , *COGNITION disorders , *DELUSIONS , *MENTAL illness , *MEMORY disorders - Abstract
False claims are a key feature of confabulation, delusion, and anosognosia. In this paper we consider the role of motivational factors in such claims. We review motivational accounts of each symptom and consider the evidence adduced in support of these accounts. In our view the evidence is strongly suggestive of a role for motivational factors in each domain. Before concluding, we widen the focus by outlining a tentative general taxonomy of false claims, including false claims that occur in clinical settings as well as more garden-variety false claims, and incorporating both motivational and nonmotivational approaches to explaining such claims. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
37. Our evolving beliefs about evolved misbelief.
- Author
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McKay, Ryan T. and Dennett, Daniel C.
- Abstract
The commentaries raise a host of challenging issues and reflect a broad range of views. Some commentators doubt that there is any convincing evidence for adaptive misbelief, and remain (in our view, unduly) wedded to our “default presumption” that misbelief is maladaptive. Others think that the evidence for adaptive misbelief is so obvious, and so widespread, that the label “default presumption” is disingenuous. We try to chart a careful course between these opposing perspectives. [ABSTRACT FROM PUBLISHER]
- Published
- 2009
- Full Text
- View/download PDF
38. The evolution of misbelief.
- Author
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McKay, Ryan T. and Dennett, Daniel C.
- Abstract
From an evolutionary standpoint, a default presumption is that true beliefs are adaptive and misbeliefs maladaptive. But if humans are biologically engineered to appraise the world accurately and to form true beliefs, how are we to explain the routine exceptions to this rule? How can we account for mistaken beliefs, bizarre delusions, and instances of self-deception? We explore this question in some detail. We begin by articulating a distinction between two general types of misbelief: those resulting from a breakdown in the normal functioning of the belief formation system (e.g., delusions) and those arising in the normal course of that system's operations (e.g., beliefs based on incomplete or inaccurate information). The former are instances of biological dysfunction or pathology, reflecting “culpable” limitations of evolutionary design. Although the latter category includes undesirable (but tolerable) by-products of “forgivably” limited design, our quarry is a contentious subclass of this category: misbeliefs best conceived as design features. Such misbeliefs, unlike occasional lucky falsehoods, would have been systematically adaptive in the evolutionary past. Such misbeliefs, furthermore, would not be reducible to judicious – but doxastically1 noncommittal – action policies. Finally, such misbeliefs would have been adaptive in themselves, constituting more than mere by-products of adaptively biased misbelief-producing systems. We explore a range of potential candidates for evolved misbelief, and conclude that, of those surveyed, only positive illusions meet our criteria. [ABSTRACT FROM PUBLISHER]
- Published
- 2009
- Full Text
- View/download PDF
39. 2′-Methyl and 1′-xylosyl derivatives of 2′-hydroxyflexixanthin are major carotenoids of Hymenobacter species
- Author
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Klassen, Jonathan L., McKay, Ryan, and Foght, Julia M.
- Subjects
- *
CAROTENOIDS , *BACTERIAL pigments , *CIRCULAR dichroism , *MASS spectrometry , *CHEMICAL structure , *ANIMAL species , *NUCLEAR magnetic resonance spectroscopy - Abstract
Abstract: Bacteria related to the genus Hymenobacter are colored intensely red due to their carotenoid pigmentation. Using high-resolution mass spectrometry and comparison to the literature reports, we previously isolated and presumptively identified seven structurally related carotenoids from representative Hymenobacter-like strains. After further analysis using one- and two-dimensional 1H NMR, UV–vis, and circular dichroism spectroscopies, we determined that the major carotenoid present in these strains is 2′-hydroxyflexixanthin, as proposed previously by others in a related organism. Furthermore, we have identified three novel, related carotenoids abundant in these strains as 1′-xylosyl-2′-hydroxyflexixanthin, 2′-methoxyflexixanthin, and 3-deoxy-2′-methoxyflexixanthin. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
40. Acute dextro-amphetamine administration does not alter brain myo-inositol levels in humans and animals: MRS investigations at 3 and 18.8T
- Author
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McGrath, Brent M., McKay, Ryan, Dave, Sanjay, Seres, Peter, Weljie, Aalim M., Slupsky, Carolyn M., Hanstock, Chris C., Greenshaw, Andrew J., and Silverstone, Peter H.
- Subjects
- *
BRAIN research , *PREFRONTAL cortex , *BIPOLAR disorder , *AMPHETAMINES - Abstract
Abstract: The pathophysiological underpinnings of bipolar disorder are not fully understood. However, they may be due in part to changes in the phosphatidylinositol second messenger system (PI-cycle) generally, or changes in myo-inositol concentrations more specifically. Dextro-amphetamine has been used as a model for mania in several human studies as it causes similar subjective and physiological symptoms. We wanted to determine if dextro-amphetamine altered myo-inositol concentrations in vivo as it would clearly define a mechanism linking putative changes in the PI-cycle to the subjective psychological changes seen with dextro-amphetamine administration. Fifteen healthy human volunteers received a baseline scan, followed by second scan 75min after receiving a 25mg oral dose of dextro-amphetamine. Stimulated echo proton magnetic resonance spectroscopy (MRS) scans were preformed at 3.0Tesla (T) in the dorsal medial prefrontal cortex (DMPFC). Metabolite data were adjusted for tissue composition and analyzed using LCModel. Twelve adult male rats were treated acutely with a 5-mg/kg intraperitoneal dose of dextro-amphetamine. After 1h rats were decapitated and the brains were rapidly removed and frozen until dissection. Rat brains were dissected into frontal, temporal, and occipital cortical areas, as well as hippocampus. Tissue was analyzed using a Varian 18.8T spectrometer. Metabolites were identified and quantified using Chenomx Profiler software. The main finding in the present study was that myo-inositol concentrations in the DMPFC of human volunteers and in the four rat brain regions were not altered by acute dextro-amphetamine. While it remains possible that the PI-cycle may be involved in the pathophysiology of bipolar disorder, it is not likely that the subjective and physiological of dextro-amphetamine are mediated, directly or indirectly, via alternations in myo-inositol concentrations. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
41. Models of misbelief: Integrating motivational and deficit theories of delusions
- Author
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McKay, Ryan, Langdon, Robyn, and Coltheart, Max
- Subjects
- *
COGNITION disorders , *SELF-perception , *TRUTHFULNESS & falsehood , *SENSES - Abstract
Abstract: The impact of our desires and preferences upon our ordinary, everyday beliefs is well-documented [. How we know what isn’t so: The fallibility of human reason in everyday life. New York: The Free Press.]. The influence of such motivational factors on delusions, which are instances of pathological misbelief, has tended however to be neglected by certain prevailing models of delusion formation and maintenance. This paper explores a distinction between two general classes of theoretical explanation for delusions; the motivational and the deficit. Motivational approaches view delusions as extreme instances of self-deception; as defensive attempts to relieve pain and distress. Deficit approaches, in contrast, view delusions as the consequence of defects in the normal functioning of belief mechanisms, underpinned by neuroanatomical or neurophysiological abnormalities. It is argued that although there are good reasons to be sceptical of motivational theories (particularly in their more floridly psychodynamic manifestations), recent experiments confirm that motives are important causal forces where delusions are concerned. It is therefore concluded that the most comprehensive account of delusions will involve a theoretical unification of both motivational and deficit approaches. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
42. Jumping to delusions? Paranoia, probabilistic reasoning, and need for closure.
- Author
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McKay, Ryan, Langdon, Robyn, and Coltheart, Max
- Subjects
- *
COGNITION disorders , *ILLUSION (Philosophy) , *DELUSIONS , *PATHOLOGICAL psychology , *PERSECUTION - Abstract
Introduction. The present study was designed to replicate and extend the findings of Bentall and Swarbrick (2003). It was hypothesised that patients with a history of persecutory delusions would display higher need for closure and a more extreme jumping to conclusions bias than healthy control participants. Methods. Twenty-two patients with a history of persecutory delusions and nineteen healthy control participants were administered a probabilistic reasoning task, along with self-report measures of depression and need for closure. Results. The clinical group scored higher on need for closure than the controls, but showed no greater tendency to jump to conclusions. No relationship was found between need for closure and a jumping to conclusions bias. Conclusions. The results confirm an association between persecutory delusions and need for closure, yet suggest that persecutory delusions in an outpatient sample can be seen in the absence of a jumping to conclusions bias. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
43. Attributional style in a case of Cotard delusion
- Author
-
McKay, Ryan and Cipolotti, Lisa
- Subjects
- *
LIFE , *NEUROLOGY , *HYPOTHESIS , *REASONING - Abstract
Abstract: Young and colleagues (e.g. Young, A. W., & Leafhead, K. M. (1996). Betwixt life and death: case studies of the Cotard delusion. In P. W. Halligan & J. C. Marshall (Eds.), Method in madness: Case studies in cognitive neuropsychiatry. Mahway, NJ: Lawrence Erlbaum Associates.) have suggested that cases of the Cotard delusion (the belief that one is dead) result when a particular perceptual anomaly (caused by a disruption to the affective component of visual recognition) occurs in the context of an internalising attributional style. This hypothesis has not previously been tested directly. We report here an investigation of attributional style in a 24-year-old woman with Cotard delusion (“LU”). LU’s attributional style (and that of ten healthy control participants) was assessed using the Internal, Personal and Situational Attributions Questionnaire (Kinderman, P., & Bentall, R. P. (1996). A new measure of causal locus: the internal, personal and situational attributions questionnaire. Personality and Individual Differences, 20(2), 261–264.). LU showed a significantly greater proportion of internalising attributions than the control group, both overall and for negative events specifically. The results obtained thus support an association of Cotard delusion with an internalising attributional style, and are therefore consistent with the account of Young and colleagues. The potential brain basis of Cotard delusion is discussed. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
44. The defensive function of persecutory delusions: An investigation using the Implicit Association Test.
- Author
-
McKay, Ryan, Langdon, Robyn, and Coltheart, Max
- Subjects
- *
DELUSIONS , *SELF-esteem , *OPPRESSION , *MENTAL depression , *ASSOCIATION tests , *MEASURES of Psychosocial Development , *PATIENTS - Abstract
Introduction. Bentall and colleagues (Bentall & Kaney, 1996; Kinderman & Bentall, 1996, 1997) claim that persecutory delusions are constructed defensively, for the maintenance of self-esteem. A central prediction of their model is that such delusions will be associated with discrepancies between overt and covert self-esteem.Methods. The present study employed a new methodology that has been widely used in investigations of implicit attitudes, the Implicit Association Test (IAT; Greenwald, McGhee, & Schwartz, 1998), to assess covert self-esteem and to test the above prediction. Overt self-esteem was assessed using the Rosenberg Self-Esteem Scale and an adjective self-relevance ratings measure. These measures were administered to 10 patients with acute persecutory delusions, 10 patients with remitted persecutory delusions, and 19 healthy control participants.Results. Patients with persecutory delusions were found to have lower covert self-esteem (as assessed using the IAT) than healthy controls and patients with remitted persecutory delusions. On two measures of overt self-esteem, however, the persecutory deluded group did not differ significantly from the other groups once the effects of comorbid depression had been taken into account.Conclusions. These results are thus consistent with a model of persecutory delusions as serving the defensive function of maintaining self-esteem. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
45. Anisotropic diffusion of metabolites in peripheral nerve using diffusion weighted magnetic resonance spectroscopy at ultra-high field
- Author
-
Ellegood, Jacob, McKay, Ryan T., Hanstock, Chris C., and Beaulieu, Christian
- Subjects
- *
ANISOTROPY , *METABOLITES , *PERIPHERAL nervous system , *MAGNETIC resonance , *SPECTRUM analysis - Abstract
Abstract: Although the diffusivity and anisotropy of water has been investigated thoroughly in ordered axonal systems (i.e., nervous tissue), there have been very few studies on the directional dependence of diffusion of metabolites. In this study, the mean apparent diffusion coefficient (Trace/3 ADC) and fractional anisotropy (FA) values of the intracellular metabolites N-acetyl aspartate (NAA), creatine and phosphocreatine (tCr), choline (Cho), taurine (Tau), and glutamate and glutamine (Glx) were measured parallel and perpendicular to the length of excised frog sciatic nerve using a water suppressed, diffusion-weighted, spin-echo pulse sequence at 18.8T. The degree of anisotropy (FA) of NAA (0.41±0.09) was determined to be less than tCr (0.59±0.07) and Cho (0.61±0.11), which is consistent with previously reported human studies of white matter. In contrast, Glx diffusion was found to be almost isotropic with an FA value of 0.20±0.06. The differences of FA between the metabolites is most likely due to their differing micro-environments and could be beneficial as an indicator of compartment specific changes with disease, information not readily available with water diffusion. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
46. Paranoia, persecutory delusions and attributional biases
- Author
-
McKay, Ryan, Langdon, Robyn, and Coltheart, Max
- Subjects
- *
PARANOIA , *PATHOLOGICAL psychology , *PSYCHOSES , *NEUROLOGY - Abstract
Abstract: An influential model of persecutory delusions put forward by Bentall and colleagues hypothesizes that persecutory-deluded patients avoid the activation of negative self-beliefs by making externalising, personalising attributions for negative events. The first study reported here used a new instrument for the measurement of persecutory ideation, the Paranoid, Persecutory and Delusion-Proneness Questionnaire, to investigate whether attributional biases are associated with subclinical persecutory ideation. The second study extended this investigation by re-examining associations between attributional biases and persecutory delusions. Both studies used the Internal, Personal and Situational Attributions Questionnaire to measure attributional style. No evidence was found for a connection between attributional biases and subclinical persecutory ideation. Furthermore, there was no support for an association between persecutory delusions and an externalising bias, and only marginal support for the hypothesized relationship between persecutory delusions and a personalising bias. These results suggest that the putative link between persecutory ideation and attributional biases only manifests (if at all) when persecutory ideation is of delusional intensity, and that it is confined to a personalising bias. [Copyright &y& Elsevier]
- Published
- 2005
- Full Text
- View/download PDF
47. “Sleights of mind”: Delusions, defences, and self‐deception.
- Author
-
McKay, Ryan, Langdon, Robyn, and Coltheart, Max
- Subjects
- *
DELUSIONS , *COGNITION disorders , *PATHOLOGICAL psychology , *PSYCHOANALYSIS , *PSYCHOLOGY , *NEUROPSYCHIATRY - Abstract
Two different modes of theorising about delusions are explored. On the one hand is the motivational approach, which regards delusions as serving a defensive, palliative, even potentially adaptive function. On the other, is the cognitive deficit approach, which conceptualises delusions as explicitly pathological, involving abnormalities in ordinary cognitive processes. The former approach, prominently exemplified by the psychoanalytic tradition, was predominant historically, but has been challenged in recent years by the latter. Some grievances against psychoanalytic theory are briefly discussed, and it is argued that although the reasons for psychoanalysis falling into scientific disrepute are partly justified, the psychodynamic notion that motivation has access to the mechanisms of belief formation is of potentially crucial theoretical utility. A variety of possible syntheses of the two theoretical modes are therefore explored, in the belief that the most comprehensive account of delusions will involve a theoretical unification of both styles of explanation. Along the way, an attempt is made to locate the notions delusion, defence, and self‐deception in a shared theoretical space. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
48. Solution structure of Cu6 metallothionein from the fungusNeurospora crassa.
- Author
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Cobine, Paul A., McKay, Ryan T., Zangger, Klaus, Dameron, Charles T., and Armitage, Ian M.
- Subjects
- *
METALLOTHIONEIN , *NEUROSPORA crassa , *FUNGI , *SPECTRUM analysis , *CYSTEINE proteinases , *ORGANOMETALLIC compounds - Abstract
The 3D-solution structure ofNeurospora crassaCu6-metallothionein (NcMT) polypeptide backbone was determined using homonuclear, multidimensional1H-NMR spectroscopy. It represents a new metallothionein (MT) fold with a protein chain where the N-terminal half is left-handed and the C-terminal half right-handedly folded around a copper(I)-sulfur cluster. As seen with other MTs, the protein lacks definable secondary structural elements; however, the polypeptide fold is unique. The metal coordinationand the cysteine spacing defines this unique fold. NcMT is only the second MT in the copper-bound form to be structurally characterized and the first containing the -CxCxxxxxCxC- motif. This motif is found in a variety of mammalian MTs and metalloregulatory proteins. Thein vitroformation of the Cu6NcMT identical to the native Cu6NcMT was dependent upon the prior formation of the Zn3NcMT and its titration with Cu(I). The enhanced sensitivity and resolution of the 800 MHz1H-NMR spectral data permitted the 3D structure determination of the polypeptide backbone without the substitution and utilization of the NMR active spin 1/2 metals such as113Cd and109Ag. These restraints have been necessary to establish specific metal to cysteine restraints in 3D structural studies on this family of proteins when using lower field, less sensitive1H-NMR spectral data. The accuracy of the structure calculated without these constraints is, however, supported by the similarities of the 800 MHz structures of theα-domain of mouse MT1 compared to the one recalculated without metal–cysteine connectivities. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
49. Energetics of the Induced Structural Change in a Ca[sup 2+] Regulatory Protein: Ca[sup 2+] and....
- Author
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McKay, Ryan T. and Saltibus, Linda F.
- Subjects
- *
MUSCLE proteins , *CALCIUM - Abstract
Examines the regulatory domains of skeletal and cardiac troponin C (sNTnC and cNTnC) upon calcium binding. Implication of E41A mutant enzyme for the calcium binding affinity of site I in sNTnC; Interaction between E41A-sNTnC with troponin I regions; Mechanism of the coupling of ligand binding involved in muscle contraction.
- Published
- 2000
- Full Text
- View/download PDF
50. Experimental and analytical investigation of contra-rotating multi-rotor UAV propeller noise.
- Author
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McKay, Ryan S., Kingan, Michael J., Go, Sung Tyaek, and Jung, Riul
- Subjects
- *
PROPELLERS , *ANECHOIC chambers , *NOISE - Abstract
• Experimentally investigated the noise and performance of contra-rotating UAV propellers. • Presented a formulation describing noise from contra-rotating propellers. • Investigated the effect of propeller diameter, speed, blade number and propeller spacing. • Tonal noise from propeller interactions is the dominant noise source. • Several methods to reduce contra-rotating UAS propeller noise are presented. Contra-rotating propellers could increase the efficiency and lifting capacity of multi-rotor unmanned aerial vehicles (UAVs); however, contra-rotating propellers can produce significant noise levels. This work experimentally investigated the noise from static contra-rotating UAV propellers in an anechoic chamber. The effects of propeller diameter were studied by testing different configurations of 12″ and 15″ propellers. The effects of propeller spacing, rotational speed and blade number were also investigated; around 1400 propeller configurations were tested in total. It was observed that interaction tones were a dominant contributor to the overall noise level, which also contained rotor-alone tones and broadband noise. A theoretical model for the far-field interaction tone noise produced by a contra-rotating propeller is presented and used to explain the tonal noise levels observed in the experimental results. It was found that the tones with a zero azimuthal mode order dominate the noise spectrum close to the propeller axis. It was shown that the amplitude and number of these tones with zero azimuthal mode order could be reduced by using contra-rotating propellers with mismatched blade numbers. It was also experimentally shown that increased spacing between the propellers generally reduced the amplitude of the interaction tones. The rate of this reduction in amplitude with spacing between the propellers was dependent on frequency and spacing. High rates of decay were generally observed at small spacings and lower rates at larger spacings. However, the decay was neither monotonic nor at a uniform rate for all frequencies, which suggests that there could be a change in the noise generation mechanism as the spacing increases. Finally, the validity of the indoor static results was demonstrated by comparing the results to an in-flight test of a quadcopter with contra-rotating propellers. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
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